1. Field of the Invention
The present invention relates to a field of collision avoidance systems, and more specifically, to a field of navigating an aircraft around a restricted air space (RAS).
2. Discussion of the Prior Art
Many commercial aircraft systems include avionics systems that prevent the pilot from instructing the plane to do maneuvers that are outside of its design envelope. For instance, Krumes et al in the U. S. Pat. No. 5,465,142, discloses xe2x80x9ca system for sensing objects in the flight path of an aircraft and alerting the pilot to their presence including a laser radar subsystem for emitting a beam of laser energy, receiving returns from objects, and processing the returns to produce range data related to the range of the objects from the aircraft. A scanning subsystem scans the beam and produces directional information related to the instantaneous direction of the beam relative to the aircraft. Processor circuitry controls operation, processes the range data and directional information with instrumentation data from the avionics system, produces video information related to the range, direction, and type of the objects, and interfaces the video information to the video display system. The processor circuitry may be programmed to (1) overlay video information on existing aircraft video display system, (2) provide acoustical warnings on an aircraft intercom, (3) analyze returns by subdividing the field of regard into a series of analysis windows, performing a statistical analysis of the returns related to each of the analysis windows, and identifying returns that fall into a common range interval, (4) transforming coordinates of objects measured relative to the aircraft to a horizon-stabilized, north-oriented coordinate system which is independent of the attitude of the aircraft, (5) inserting the coordinates of identified objects into a data base so that the coordinates may be used for constructing a video display at a later time and updating the data base to correct for movements of the aircraft, and (6) constructing a window-of-safety display of objects currently within the field of regard by adjusting the displayed position of the objects to compensate for avoidance maneuvers the pilot may execute.xe2x80x9d In addition, the U. S. Pat. No. 6,161,063, issued to Deker, describes xe2x80x9ca method of automatically controlling an aircraft to avoid a vertical zone including several steps. The aircraft first acquires limits of the zone to be avoided. The zone is modeled by a cylindrical volume which is limited by a horizontal contour with upper and lower altitudes of the zone. The cylindrical volume associated with a scheduled route of the aircraft is located and points of entry and exit in the cylindrical volume are determined. A new flight altitude is calculated in order to avoid the zone. A point of change of altitude is calculated to reach an avoidance altitude. The new flight altitude is updated and the point of change of altitude is input into an automatic pilot.xe2x80x9d
However, it is become useful for an aircraft to have an on-board navigational system that would prevent the aircraft from entering a predetermined restricted airspace (RAS) in the event that the pilot could not take an appropriate evasive action on his own, for whatever reason. For example, a restricted airspace (RAS) can include a mile horizontal, and a thousand feet vertical of previously-defined spaces. The properly designed on-board navigation-control system should also limit the velocity and acceleration vectors of an aircraft when the aircraft is within a prescribed range to the RAS.
It is become also very useful to have an on-board tamper-proof or tamper-resistant navigational system that would prevent the pilot from entering a predetermined RAS, and that is very difficult to tamper with, or circumvent. However, a pilot with a valid identity authentication should be able to override the on-board tamper-proof or tamper-resistant navigational system in certain emergency cases. Thus, the on-board tamper-proof navigational system should be able to operate in at least two modes: (a) non-overriding mode, when the pilot can not override the on-board tamper-proof/tamper-resistant navigational system that would prevent the pilot from entering a predetermined RAS; (b) overriding mode, when the pilot upon proper authentication of his identity, is able to override the on-board tamper-proof/tamper-resistant navigational system and take control of the aircraft despite there being a possibility of entering a restricted airspace, presumably with the goal of flying around it himself instead of letting the navigational system fly the plane.
To address the shortcomings of the available art, the present invention provides a tamper-proof/tamper-resistant apparatus located on board of an aircraft for avoiding a restricted air space (RAS). Tamper-proof and tamper-resistant are used interchangeably as the term might apply to each component in the system. Some components may be truly tamper-proof, while others can only achieve tamper-resistance. That is, the component cannot ever be made truly tamper-proof.
In one embodiment of the present invention, a tamper-proof apparatus located on board of an aircraft for avoiding a restricted air space (RAS) comprises: (1) a tamper-proof restricted air space (TAP-RAS) database configured to include a set of coordinates that determines the RAS; and (2) a navigational processor configured to navigate the aircraft around the RAS, if a valid overriding command is not generated. If a valid overriding command is generated, the navigational processor is configured to navigate the aircraft in an overriding mode. In one embodiment when the valid overriding command is implemented, the navigational processor can continue to fly the plane to avoid the RAS; the pilot can make minor adjustments as he sees fit, or can take over control entirely, at his discretion. Alternatively, while being in the overriding mode, the navigational processor can be configured to navigate the aircraft in such a way as to penetrate the RAS. This event cannot be avoided if a valid overriding authorization is entered by an authentic and approved pilot.
In one embodiment of the present invention, the navigational processor further comprises: (a) a Satellite Positioning System (SATPS) configured to substantially continuously obtain a set of real time position coordinates of the aircraft; (b) a restricted airspace controller configured to receive and analyze a set of real time data including the set of coordinates that determines the RAS and the set of real time position coordinates in order to substantially continuously generate a real time set of commands; and (c) an aircraft controller configured to navigate the aircraft utilizing the real time set of commands around the RAS.
In one embodiment, the restricted airspace controller is configured to receive and analyze a set of real time data including the set of coordinates that determines the RAS and the set of real time position coordinates in order to substantially continuously generate the likelihood of penetration of the RAS based on the current flight path, RAS position, and the current speed and acceleration of the aircraft. In this embodiment, the restricted airspace controller generates a set of real time commands for executing evasive maneuvers to avoid the RAS, and an estimate of the flight time until such execution should begin.
The Satellite Positioning System (SATPS) further includes: a Global Positioning System (GPS), a Global Navigational System (GLONASS), or a combined GPS/GLONASS system.
In one embodiment, the Global Positioning System (GPS) further includes a differential Global Positioning System (DGPS) configured to receive a set of differential corrections in order to substantially continuously obtain a set of real time position coordinates of the aircraft with increased accuracy. In one embodiment, the differential Global Positioning System (DGPS) further includes a velocity block configured to substantially continuously obtain a set of real time velocity vectors of the aircraft, and an acceleration block configured to substantially continuously obtain a set of real time acceleration vectors of the aircraft.
In one embodiment, the restricted airspace controller further includes a message block configured to substantially continuously generate a set of real time messages; wherein a pilot warning device is configured to receive this set of real time warning messages, and configured to present this set of warning messages in audio and/or visual format.
In one embodiment, the navigational processor located on board of an aircraft is configured to substantially continuously receive a set of real time signals including the position coordinates of the RAS from at least one anti-spoof and anti-jam pseudolite located in the RAS. In this embodiment, the anti-spoof and anti-jam pseudolite is configured to substantially continuously transmit a set of real time pseudolite signals including the position coordinates of the pseudolite itself and a buffer range data set defining around the RAS to the navigational processor located on board of an aircraft.
In one embodiment of the present invention, the anti-spoof and anti-jam pseudolite located in the RAS includes a split-spectrum pseudolite that is configured to substantially continuously transmit a set of real time split-spectrum pseudolite signals including the position coordinates of the pseudolite and a buffer range data set defining around the RAS. The set of split-spectrum signals is configured to minimize interference with the reception of satellite signals by the satellite receiver located on board of the aircraft.
In one tamper-proof embodiment of the present invention, the navigational processor comprises a tamper-proof navigational processor. In this embodiment of the present invention, the tamper-proof navigational processor further includes: (a) a tamper-proof/tamper resistant Satellite Positioning System (TAP-SATPS) configured to substantially continuously obtain a set of real time position coordinates of the aircraft; (b) a tamper-proof restricted airspace controller configured to receive a set of real time data including the set of coordinates that determines the restricted air space, the set of real time position coordinates; and configured to analyze the set of real time data in order to substantially continuously generate a real time set of commands; and (c) a tamper-proof aircraft controller configured to receive the real time set of commands and configured to navigate the aircraft utilizing the real time set of commands around the RAS.
In one embodiment, the tamper-proof restricted airspace controller is configured to calculate a vector from based on the current flight path of the aircraft and determines if that vector intercepts the RAS at any point of the surface of the RAS; if such a penetration of the RAS surface, as defined by the RAS database, occurs, an emergency warning is issued to the cockpit both audibly and/or visually to warn the pilot. In another embodiment, the tamper-proof restricted airspace controller is configured to determine the amount of time necessary to make evasive maneuvers, and the point in space and time whereby these maneuvers should begin in order to avoid penetrating the RAS, and is configured to calculate the time remaining before such maneuvers should begin.
The tamper-proof/tamper-resistant Satellite Positioning System (TAP-SATPS) can further include: a tamper-proof/tamper-resistant Global Positioning System (TAP-GPS), a tamper-proof/tamper-resistant Global Navigational System (TAP-GLONASS), or a tamper-proof/tamper-resistant combined GPS/GLONASS system (TAP-GPS/GLONASS).
In one embodiment, the tamper-proof Global Positioning System (TAP-GPS) further includes a differential tamper-proof Global Positioning System (DIF-TAP-GPS) configured to receive a set of differential corrections in order to substantially continuously obtain a set of real time position coordinates of the aircraft with increased accuracy. In one embodiment, the differential tamper-proof Global Positioning System (DIF-TAP-GPS) further includes a velocity block configured to substantially continuously obtain a set of real time velocity vectors of the aircraft, and an acceleration block configured to substantially continuously obtain a set of real time acceleration vectors of the aircraft.
In one embodiment, the tamper-proof restricted airspace controller further includes a message block configured to substantially continuously generate a set of real time messages; wherein a pilot warning device is configured to receive this set of real time warning messages, and configured to present this set of warning messages in audio and/or visual format.
In one embodiment, a tamper-proof satellite receiver located on board of an aircraft is configured to substantially continuously receive a set of real time signals including the position coordinates of the RAS in order to navigate the aircraft around the RAS. In one embodiment, the tamper-proof satellite receiver located on board of an aircraft receives the position coordinates from at least one anti-spoof and anti-jam pseudolite located in the RAS that is configured to substantially continuously transmit a set of real time pseudolite signals including its own position coordinates and the position coordinates of a buffer range data set further defining around the RAS.
In one embodiment, the anti-spoof and anti-jam pseudolite located in the RAS includes a split-spectrum pseudolite that is configured to substantially continuously transmit a set of real time split-spectrum pseudolite signals including the position coordinates of the pseudolite and a buffer range around the RAS. The set of split-spectrum signals is configured to minimize interference with the reception of satellite signals by the tamper-proof/tamper-resistant satellite positioning receiver located on board of the aircraft.
In one embodiment of the present invention, the on-board apparatus further includes an overriding processor configured to generate a valid overriding command. In one embodiment, the overriding processor further includes a biometric authentication sensor configured to validate the overriding command upon verifying the authenticity of an overriding person with the authority to initiate an over-ride command, for instance an authenticity of a pilot whose identity and biometric indicia are stored in the overriding processor or the biometric authentication sensor, that issues the overriding command. In one embodiment of the present invention, the biometric authentication sensor is a sensor selected from the group consisting of an eye retina authentication sensor, a voice authentication sensor, a palm authentication sensor, and a face recognition sensor.
Another aspect of the present invention is directed to a method for navigating an aircraft around a restricted air space (RAS). In one embodiment, the method for navigating an aircraft comprises the following steps: (1) navigating the aircraft around a restricted air space (RAS) in a restricted air space mode (RAS-mode); if a valid overriding command is not generated; and (2) navigating the aircraft in an overriding mode (RAS-override-mode); if the valid overriding command is generated.
In one embodiment of the present invention, the step of navigating the aircraft around the RAS in the RAS-mode further includes the following steps: (1) substantially continuously obtaining a set of coordinates that defines the RAS; (2) substantially continuously obtaining a set of real time position coordinates of the aircraft; and (3) analyzing a set of real time data including the set of coordinates that determines the RAS, and the set of real time position coordinates of the aircraft in order to substantially continuously generate a real time set of commands for navigating the aircraft away from or around the RAS.
In one embodiment of the present invention, the step of navigating the aircraft around the RAS in the RAS-mode further includes the steps of: (a) continuously monitoring whether the tamper-proof on-board apparatus was tampered with; and (b) if the tamper-proof apparatus on-board was tampered with, sending a set of monitoring data to a ground controller using an aircraft-ground link. In one embodiment of the present invention, the set of monitoring data is selected from the group consisting of: a flight information, an aircraft ID number, a time coordinate when the tampering event occurred, a set of position coordinates of the aircraft at the time coordinate when the tampering event occurred, and a speed vector of the aircraft at the time coordinate when the tampering event occurred.
In one embodiment of the present invention, when the valid overriding command is generated, the step of navigating the aircraft in such overriding mode (RAS-override-mode) further includes the steps of: verifying an authenticity of the pilot identity; and generating the valid overriding command by using an overriding processor, if the authenticity of the pilot identity is established.